1 #include <stdio.h> 2 #include <stdlib.h> 3 #include <time.h> 4 #include <math.h> 5 #include <string.h> 6 #include <unistd.h> 7 #include <sys/types.h> 8 #include <sys/stat.h> 9 10 #include "../lib/lfsr.h" 11 #include "../gettime.h" 12 #include "../fio_time.h" 13 14 void usage() 15 { 16 printf("Usage: lfsr-test 0x<numbers> [seed] [spin] [verify]\n"); 17 printf("-------------------------------------------------------------\n"); 18 printf("*numbers: how many random numbers to produce (in hex)\n" 19 "seed: initial value\n" 20 "spin: how many iterations before we produce a number\n" 21 "verify: check if LFSR has iterated correctly\n\n" 22 "Only <numbers> is required. The rest are evaluated to 0 or false\n" 23 "Elapsed/mean time and verification results are printed at the" 24 "end of the test\n"); 25 } 26 27 int main(int argc, char *argv[]) 28 { 29 int r; 30 struct timeval start, end; 31 struct fio_lfsr *fl; 32 int verify = 0; 33 unsigned int spin = 0; 34 uint64_t seed = 0; 35 uint64_t numbers; 36 uint64_t v_size; 37 uint64_t i; 38 void *v = NULL, *v_start; 39 double total, mean; 40 41 /* Read arguments */ 42 switch (argc) { 43 case 5: if (strncmp(argv[4], "verify", 7) == 0) 44 verify = 1; 45 case 4: spin = atoi(argv[3]); 46 case 3: seed = atol(argv[2]); 47 case 2: numbers = strtol(argv[1], NULL, 16); 48 break; 49 default: usage(); 50 return 1; 51 } 52 53 /* Initialize LFSR */ 54 fl = malloc(sizeof(struct fio_lfsr)); 55 if (!fl) { 56 perror("malloc"); 57 return 1; 58 } 59 60 r = lfsr_init(fl, numbers, seed, spin); 61 if (r) { 62 printf("Initialization failed.\n"); 63 return r; 64 } 65 66 /* Print specs */ 67 printf("LFSR specs\n"); 68 printf("==========================\n"); 69 printf("Size is %u\n", 64 - __builtin_clzl(fl->cached_bit)); 70 printf("Max val is %lu\n", (unsigned long) fl->max_val); 71 printf("XOR-mask is 0x%lX\n", (unsigned long) fl->xormask); 72 printf("Seed is %lu\n", (unsigned long) fl->last_val); 73 printf("Spin is %u\n", fl->spin); 74 printf("Cycle length is %lu\n", (unsigned long) fl->cycle_length); 75 76 /* Create verification table */ 77 if (verify) { 78 v_size = numbers * sizeof(uint8_t); 79 v = malloc(v_size); 80 memset(v, 0, v_size); 81 printf("\nVerification table is %lf KBs\n", (double)(v_size) / 1024); 82 } 83 v_start = v; 84 85 /* 86 * Iterate over a tight loop until we have produced all the requested 87 * numbers. Verifying the results should introduce some small yet not 88 * negligible overhead. 89 */ 90 fprintf(stderr, "\nTest initiated... "); 91 fio_gettime(&start, NULL); 92 while (!lfsr_next(fl, &i)) { 93 if (verify) 94 *(uint8_t *)(v + i) += 1; 95 } 96 fio_gettime(&end, NULL); 97 fprintf(stderr, "finished.\n"); 98 99 100 /* Check if all expected numbers within range have been calculated */ 101 r = 0; 102 if (verify) { 103 fprintf(stderr, "Verifying results... "); 104 for (i = 0; i < numbers; i++) { 105 if (*(uint8_t *)(v + i) != 1) { 106 fprintf(stderr, "failed (%lu = %d).\n", 107 (unsigned long) i, 108 *(uint8_t *)(v + i)); 109 r = 1; 110 break; 111 } 112 } 113 if (!r) 114 fprintf(stderr, "OK!\n"); 115 } 116 117 /* Calculate elapsed time and mean time per number */ 118 total = utime_since(&start, &end); 119 mean = total / fl->num_vals; 120 121 printf("\nTime results "); 122 if (verify) 123 printf("(slower due to verification)"); 124 printf("\n==============================\n"); 125 printf("Elapsed: %lf s\n", total / pow(10,9)); 126 printf("Mean: %lf us\n", mean); 127 128 free(v_start); 129 free(fl); 130 return r; 131 } 132
